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When to bless a Perl variable

Perl's bless function, which turns a reference into an instance of an object, it typically called up as the last action in a constructor method. On today's Perl for Larger Projects course, I was challenged as to when else it might be used. Here's an example - when loading a file of information into objects, in a method that's returning a whole list of objects:


sub fileload {
my ($class,$fname) = @_;
open (FH,$fname);
my @result;
while (<FH>) {
my ($thisclass,$breed,$age,$equiv) = split;
my %self;
$self{breed} = $breed;
$self{age} = $age;
$self{equiv} = $equiv;
push @result, bless \%self,$thisclass;
}
return @result;
}


Interesting, this code's also an example of the two parameter use of bless, where an object is being blessed into a class that's not got the same name as the current package.
(written 2005-03-15, updated 2006-06-05)

 
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P213 - Perl - Creating your own Classes
  [4607] Classes and object - first steps in Perl 6 - (2016-01-02)
  [3833] Learning to use existing classes in Perl - (2012-08-10)
  [3098] Learning Object Orientation in Perl through bananas and perhaps Moose - (2010-12-21)
  [3059] Object Orientation in an hour and other Perl Lectures - (2010-11-18)
  [2969] What does blessing a variable in Perl mean? - (2010-09-24)
  [2877] Further more advanced Perl examples - (2010-07-19)
  [2834] Teaching examples in Perl - third and final part - (2010-06-27)
  [2169] When should I use OO techniques? - (2009-05-11)
  [1925] Introduction to Object Oriented Programming - (2008-12-06)
  [1864] Object Oriented Perl - First Steps - (2008-11-01)
  [1664] Example of OO in Perl - (2008-06-03)
  [1435] Object Oriented Programming in Perl - Course - (2007-11-18)
  [1320] Perl for Larger Projects - Object Oriented Perl - (2007-08-25)
  [983] Blessing in Perl / Member variable in Ruby - (2006-12-14)
  [975] Answering ALL the delegate's Perl questions - (2006-12-09)
  [227] Bellringing and Programming and Objects and Perl - (2005-02-25)

P218 - Perl - More Objects
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  [4356] Object factories in C++, Python, PHP and Perl - (2014-12-19)
  [4098] Using object orientation for non-physical objects - (2013-05-22)
  [4096] Perl design patterns example - (2013-05-20)
  [3941] Building an object based on another object in Perl - (2012-12-03)
  [3581] Perl - calls to methods that use => - what do they mean? - (2012-01-16)
  [3377] What do I mean when I add things in Perl? - (2011-08-02)
  [3097] Making Perl class definitions more conventional and shorter - (2010-12-20)
  [2972] Some more advanced Perl examples from a recent course - (2010-09-27)
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  [588] Changing @INC - where Perl loads its modules - (2006-02-02)
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